1995 Ford Windstar Won't start, no fire.

The coil pack has a four wire connector plugged into it. One of the wires (usually RED) is the 12v supply wire. Unplug that connector and use a digital voltmeter to check for 12v on that wire with the ignition switch turned on.
If 12v is present, you'll have to check the crankshaft sensor next (more on that in a minute).
If there is not 12v present, check the ignition fuse #20 (which is a 25A fuse) and/or ignition relay.

To check the crankshaft sensor:

The Crank Sensor is located right behind the Crankshaft Pulley it's reluctur ring is part of the crankshaft pulley.

1. With the vehicle properly raised and supported, use a wire piercing tool to tap into the two crankshaft sensor wires.
2. Attach the two leads of a digital voltmeter to the two crankshaft sensor wires (it doesn't matter which leads goes on which wire).
3. Set the voltmeter to the AC scale (2V AC max if the meter has that scale). If not, either Ac scale will do.
4. With leads well away from all rotatiing engine parts, have a patner to spin the engine, as if tryin to start it for about 10 seconds.
5. The voltmeter should read between.5 and 1 volt AC (the meter will jump between.5 and 1 volt AC as the engin e is being cranked).
6. If you have the proper voltage, the crankshaft sensor if OK.

Note: If you had a spark at either of the spark plug wires when you checked the coil pack, then the crankshaft sensor if good and there is no need to test it.

Please post your results and advise us of any further assistance needed.
Thanks.